Heat Exchanger Brazing Layout to Prevent Member Misalignment

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Heat exchangers manufactured using furnace brazing often experience member misalignment due to load application during assembly, leading to shifted positions of fins, heat transfer pipes, and headers during the brazing process.

Innovation Solution

A heat exchanger manufacturing method where the protruding length of fins from heat transfer pipes and the distance from heat transfer pipes to headers are set equal, allowing for uniform contact and minimizing inclination during furnace brazing, ensuring each member remains in its original position.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If furnace brazing is performed with heat exchanger members temporarily assembled on a conveyer, then the manufacturing process can be completed, but the fins, heat transfer pipes, or headers are brazed in a state shifted from original positions due to load application

Engineering Contradiction:
Improvemanufacturing process completionVSAvoidposition accuracy of members
Core Design Contradiction:
ProductivityVSManufacturing precision

Solution Approach 1:

The protruding lengths of fins and distances from heat transfer pipes to headers are set equal in advance before brazing. This preliminary dimensional configuration ensures uniform contact with the conveyer surface, preventing position shifts during the brazing process and maintaining manufacturing precision while enabling continuous production

Inventive Principle:
Principle #10Preliminary action

2Stability of the object's composition

If the protruding length of fins and distance to headers are set equal, then uniform contact is achieved and position stability is improved, but additional assembly steps are required

Engineering Contradiction:
Improveposition stability during brazingVSAvoidassembly process complexity
Core Design Contradiction:
Stability of the object's compositionVSDevice complexity

Solution Approach 1:

The invention changes the dimensional parameters of the heat exchanger components by setting the protruding length of fins and the distance from heat transfer pipes to headers to be equal. This parameter adjustment enables uniform contact with the conveyer surface, improving position stability during brazing while the modular design keeps the assembly process manageable

Inventive Principle:
Principle #35Parameter changes

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

This method reduces deformation and clearance issues, enhancing assemblability and maintaining performance by maintaining the original position of heat exchanger components during brazing.

Implementation Method 1

conveying the assembled member into a furnace by the conveyer to heat the assembled member, thereby performing brazing of the assembled member

Methodology Applied
Scientific EffectHeating: Heating

Data Source

PatentEP3657117B1Heat-exchanger manufacturing method, heat-exchanger overlaying method, heat exchanger and multi-row heat exchanger
Publication Date: 2024.03.13 HITACHI JOHNSON CONTROLS AIR CONDITIONING INC
  • EP3657117B1 patent drawingFigure 1(a)~1(b)
  • EP3657117B1 patent drawingFigure 2~3(c)
  • EP3657117B1 patent drawingFigure 4~5

AI summary

A heat exchanger includes fins (2), heat transfer pipes (3), and headers (4). These members are joined to each other by brazing. The fins (2), the heat transfer pipes (3), and the headers (4) are assembled and placed on a conveyer (101) with longitudinal directions of the headers (4) and the fins (2) being a horizontal direction. In this state, the protruding length Tf of the fin (2) from the heat transfer pipe (3) and a distance Th from the heat transfer pipe (3) to an outer surface of the header (4) on the same side as the protrusion are substantially equal to each other.